Teratology study of two isoglutamine derivatives.

The embryotoxicity and teratogenicity of N-phthalyl isoglutamine (2), a metabolite of thalidomide, and of "K-2004-1c", 2-(bicyclo[2.2.1]heptane-2-endo-3-endo-dicarboximido)-glutaric acid 1-amide (4), the main metabolite of the test compound "K-2004" (proposed generic name: biglumide), a nonteratogenic congener of thalidomide, have been investigated in mice and rats. Whereas 2 proved to be highly teratogenic and embryotoxic, 4 showed none of these activities in the dose range from 50 to 400 mg/kg.